Toaster



Jan. 14, 1947. R. E. BARcLAY TOASTER 4 Sheets-Sheet 1 Filed Sept. 7,1944 Jan. 14, 1947. R, E, BARCLAY TOASTER Filed sept. 7, 1944 4Sheets-Sheet 2 Jan. 14, 1947. R E BARCLAY 2,414,081

TOASTER Filed Sept. 7, 1944 4 Sheets-Sheet I5 Jan. 14, 1947. R. E.BARCLAY TOASTER Filed Sept. 7, 1944 4 Sheets-Sheet 4 Patented Jan. 14,1947 UNITED STATES PATENT oFFicE TOASTER Robert E. Barclay, Chicago,Ill., assignor to Federal Electric Company, Inc., Chicago, IlL, acorporation of New York Application September 7, 1944, Serial No.552,971

3 Claims. l

This invention relates to toasters, and is more particularly concernedwith toasters embodying toast carriers movable from a loading positionto a toasting position by manual operative means and automaticallymovable from their toasting positions to their loading positions after apredetermined interval of time.

It is an object of the present invention to provide a toaster embodyingimproved means for controlling the interval of time during which thetoast carriers,I are maintained in their toasting positions. It is afurther object of this invention to provide a toaster embodying improvedheater units for directing heat against toast carried by the toastcarriers when same are disposed in their toasting positions.

A further object of this invention is to provide means for automaticallydisconnecting the heaters from a source of current upon movement of thetoast carriers from their toasting positions to their loading positions.

Another object of this invention resides in the provision of an improvedtoast carrier and improved means for actuating same between its loadingand toasting position.

A further object of this invention is to provide improved heater unitsembodying reflector plates by means of which heat may be retlected fromheat receiving elements toward the toast carrier.

Another object of this invention is to provide a toast carrier movablebetween toasting and loading positions without the use of springs. Inthe present invention the toast carrier is movable by manual operativemeans from a loading position to a toasting position and isautomatically returned to its loading position by means ofcounterweights preferably mounted thereon.

It is a further object of this invention to provide an improved electriccircuit for controlling the operation of the heater elements and therelays of the toast carriers from their toasting position to theirloading position. The present invention contemplates the use of anelectronic discharge device included inthe circuit with a capacitanceand a variable resistance unit, in which a negative potential isimpressed on the grid of the electric discharge device for maintainingsame ,non-conducting for a predetermined interval of time.

This invention further contemplates the provision of an electric controlcircuitwhich is operable'with either alternating or direct current forreleasing the tast carriers from their toasting positions anddisconnecting the heating elements from the source of current. In theuse of rent, therefore, a neo'n glow lamp is included in the electricalcircuit for indicating to the user the polarity of the current.

This invention embodies other novel features, details of constructionand arrangement of parts which are hereinafter set forth in thespecification and claims and illustrated in the accompanying drawingswherein:

Fig. 1 is a sectional view taken along the line I-I of Fig. 2 showingthe toaster embodying features oi this invention.

Fig. 2 is a sectional view taken along the line 2-2 of F18. 1.

Fig. 3 is a detailed side elevational view showing a heater unit.

Fig. 4 is a sectional view of same taken along the line 4--4 of Fig. 3.

Fig. 5 shows the electrical timing circuit employed for controlling themovement of the toast carriers and the operation oi the heating units.

Fig. 6 is a fragmentary sectional view showing a modified form of thisinvention in which the toast carrier is actuated by means of a rack anda pair of gears.

Referring now to the drawings for a better understanding of thisinvention, a toaster is shown as comprising a pair of toast carriers -Iland i2 provided with ears i3 for engagement on a cross shaft I4. Theshaft I4 is journaled in a pair of bearings I6 which in turn are securedto a base Il by means of angle brackets i8 and screws I9.

Each toast carrier comprises an angle shaped plate 2| and side rail wiremembers 22 for holding a slice of toast indicated at 23 against lateraldisplacement from the toast carrier. The toast carriers are pivotallymovable for joint movement from a loading position to a toastingposition, as indicated in Fig. l, by means of an operating lever 24which is journaled on a pin 26 and acts through connecting links 21 anda lever 28.

A pair of heater units 3i are provided for each toast carrier and aresupported on the base Il by means of supporting brackets 32 and rivets33. Each heater unit comprises a reflector plate 30 formed of metal andchromium plated to receive a sheet of mica 34 and a plurality of heatingelements 36. Each heating element comprises a rectangular sheet of mica31 having a resistance Wire 38 wound thereon, said wires being connectedin a series and leading to suitable terminals 39 for connection throughleads 40 to a. source of current.

. withthe terminal i.

Vof contact with a pair of terminals 62.

A suitable housing 4| is mounted on the base I1 and formed with a pairof openings 42 in the front face thereof through which slices of toastmay be inserted for positioning on the toast carriers Ii and i2.

The toast carriers li and i2 are movable from their loading positions totheir toasting positions by downward movement of the free end of theoperating lever 24 which acts through the connecting links 21 andlever'28 to pivot'the shaft I5. As the toast carriers approach theirtoasting positions, a switch actuating arm 46 provided on the toastcarrierv Ii acts against a bell crank lever 41 to move the switch 48 outof contact with the terminal 49 and into contact with the terminal 5land also to move the switch 52 out of contact After the pressure isremoved from the free end of the operating lever 24, the toast carriersil and i2 are adapted to move a short distance towards their loadingposition due to the action of the counterweights 53 provided on theforward ends. of the toast carriers. This movement of the toast carrierstoward their loading positions permits the switches 58 and 52 to moveback into contact with their respective terminals 49 and 5i. Furthermovement of the toast carriers Il and i 2 toward their loading positionsis prevented by means of a latch 54 which engages -under an abutmentshoulder 56 provided on an armature 51. The armature 51 is pivotallyconnected at 58 toa supporting bracket 59 and carriers a switch 6i formovement into and out The switch 6l is normally in engagement with theterminals 62 and is adapted to be moved out of engagement therewith tobreak the circuit through the leads 49 by energization of the relay 63.When the relay 63 is energized it acts to pivot the armature 51 towardssame, thereby moving the switch 6l out of contact with the terminals 62and also moving the abutment shoulder 56 out of engagement with thelatch 55. The circuit 40 to the heating units 3i is thus broken, and thetoast carriers are unlatched and free to move from their toastingpositions to their loading positions.

The improved circuit for energizing the relay 63 includes an electricdischarge device 66 and preferably a high vacuum tube having a cathode61, a control grid 68, a screen grid 69 and an anode 1i. A pair of leads12 and 13 are employed to direct either alternating or direct current tothe terminals 5l and 14 respectively. The terminal 49 is connected tothe control' grid 68 by lead 16, and the terminal 5i leads throughswitch 524 and lead 11 to the cathode 61. A lead 18 -extends from theswitch 48 to one side of the capacitance 19, and the other side of thecapacitance is connected by a lead 8l to the lead 11. A

rxed resistance 82 and a variable resistance 83 are connected in aseries between the leads 16 and 11. A s witch 84 leads from the terminal14 through a lead 86 to the screen grid 69 and relay 63, and the relayis also connected to the anode -1l by means of a lead 81.A If desired acapaciis accumulated on the plates thereof by virtuev 4 terminal 5i tocharge the capacitance 19. A portion of the negative charge of thecapacitance 19 of the anode and screen grid rectification current whichiiows between the cathode 61 and the anode and screen grid. Thecondenser 19 preventsow of su'icient anode current to actuate relay 63.When the operators hand is removed from the operating lever 24, thetoast carrier moved a short distance towards its loading position untilengaged against further movement by the latch 59 and the shoulder 56 ofthe armature 51. This movement is sufcient to permit the switches 98 and52 to again move into'engagement with their respective terminals 49 and5|. Upon return of the switches 48 and 52 to their normal positions inwhich contact is made with the terminals 49 and 5i respectively, theelectric discharge device 66 will not conduct current for apredetermined interval of time established by the constants of thecircuit. The length or duration of the minimum and maximum time delayintervals depends upon a number of factors, the principal ones being thevalue of the capacitance 19 and the value of the resistances 82 and 83.The electric discharge device 56 is maintained non-conducting for apredetermined interval of time due to the negative voltage impressed onthe grid 68 by virtue of the charge of the capacitance 19. l

Immediately after the closure of switches 48 and 52 and for apredetermined interval of time thereafter, depending upon the setting ofthe system, the negative uni-directional component provided by thepre-charge of the capacitance 19 predominates and therefore maintainsthe electric discharge device 66 non-conducting. This negativeuni-directional' component of lvoltage produced by capacitance 19immediately begins to decrease in magnitude upon return of the switches48 and 52 to their normal positions indicated in Fig. 5. After apredetermined interval of time the negative potential of the grid 68becomes sufficiently low with respect to the cathode of the dischargedevice 66 that the device conducts suicient current to operate. Therelay 63 thus acts to open the circuit 40 a predetermined interval oftime alter movement of the switches 48 and 52 to their positionsindicated in Fig. 5 of the drawings.. The energization of the relay 63also actuates the armature 51 to move the abutment shoulder 56 out ofengagement with the latch 54, thus permitting the counterweights 53 topivot the toast carriers Il and i2 back to their loading positions.

As the timing circuit thus described is operative with eitheralternating or direct current, a neon glow lamp 9| is connected betweenthe leads 12 and 13 to indicate to the user the proper positioning of aconnecting plug with a socket (not shown). When the device is used withalternating current both elements 92 and 93 of the lamp 9i are adaptedto be illuminated by the current passing therethrough, however, when thedevice is employed with direct current only one of the elements, 92 or93, will become illuminated depending upon the polarity of the current.In order that the electric circuit may be operative with direct current,it is essential that proper polarity is provided, in which event theelement 92 will be be illuminated and the user will be advised by meansof instructions printed upon the toaster that a proper connection hasbeen made between the plug and the outlet.

The interval of time during-which the toast carriers I I and I2 are heldin their toasting positions may be varied by adjustment o! the variableresistancev83. 'Y Y l Fig. 6 shows a modified iorm of this invention inwhich the toast carriers il and I2 are pivoted from theirloadingpositions to their toasting positions by means of an operatingrack lill which acts through anintermediate gear |02 to rotate a gear|03 secured to the toast carrier shaft I4. This form of the invention isotherwise similar to the form heretofore showny yand described.

In the use of a toaster of the type thus described, it will be observedthat' the toast carriers and the actuating'means therefor arefrelatively simple in operation, inexpensive in construction and will'notreadily get out `oi', order,l Y Iiii'rther, that the use ofchromiumplated reiiector plates with the heating elements vserves toradiate the heat towards thetoast carrier 'and are adapted to conserveelectrical energy and to facilitate the toasting operation. l

By means of the electrical circuit employed with the toaster, the breadAmay be suitably toasted for a .predetermined intervaiof time to suit therequirements of the operator by merely turning a control knob foradjusting the variable resistance 83. Due. to the fact that alternatingand direct current are both commonly employed, itis essential to providea circuit adapted for use with either type oifonrrent, and while thiscircuit is adapted formusefwith toasters, it is contemplatedthat' itbeemployed` for use with devices'lotherthanto s` for operating a relay,solenoid'orthelike. f Y

While this invention-nas been lshown in but two forms, `itisqobvioustothose` skilled in the art that it is not solimitedbut is. susceptible ofvarious changes and modincations without d'eparting from the spirit theappended claims. l I claim as my invention:

thereof or the scope Vof -1. In a toaster, a toast carrier movablebetween a toasting and a non-toasting position, heating elements fordirecting heat against material to be 6 said condenser is charged tosaid predetermined value and for deenergizing said heating elements andcausing said toast carrier to move to nontoasting position when thecharge on said condenser decreases to another predetermined value.

2. In a toaster, a toast carrier movable between toasting andnon-toasting position, heating elements for directing heat againstmaterial to be toasted in said toast carrier when the latter is intoasting position, means urging said carrier to non-toasting position,holding means for holding said carrier in toasting position, controlmeans for releasing said holding means a predetermined time after saidtoast carrier has been manually moved to toasting position, said controlmeans including an electron tube having an anode,' ,a cathode and acontrol grid, an amode-cathode circuit having conductors for connectingsaid tube Ito a source of electric power, a condenser normally connectedbetween said cathode and said grid,

switch means actuated by movement of Said toast carrier to toastingposition for momentarily connecting said condenser in series in saidanodecathode circuit to charge said condenser and then reconnect saidcondenser between said cathode and grid to impress a negative potentialon said grid relative .to said cathode, a resistor connected across saidcondenser .to provide for gradual decrease of said charge, and meansresponsive to current flow in said anode-cathode circuit due to decreasein said charge for releasing said holding means after a predeterminedtime interval.

3. In a toaster, a toast-carrier movable between toasting andnon-toasting position, heating eletoasted in said toastcarrie'r'when thelatter is a in said toasting position, control means in said toaster forholding said carrier in toasting position and causing movement oi'saidcarrier to nontoasting position after ls, predetermined time inl mentsfor directing heat againstvmaterial'to betoasted in said toast carrierwhen the latter is in toasting position, means urging said carrier tonon-toasting position, holding means for holding said carrier intoasting position, control -means for releasing said holding means apredetermined time after said toast carrier has been manually moved totoasting position, said control means including an electron tube havingan anode, a cathode and a control grid, an anodecathode circuit havingconductors for connecting said tube to a source of electric power, acondenser normally connected between said cathode and 4 saidgrid, switchmeansy actuated by movement of terval, said toasting means includinganelectron tube having an anode, a cathode and a control grid, la controlcircuit including an anode-cathode circuit having conductors'for'connecting said tube to a source oLelectric power. Va :'i"ndex'i.-ierin said control circuit for controlling the potential; oi'said gridrelative to said cathode-'fin' accord-jA said toast carrier to toastingposition for momentarily connecting said condenser in series in saidanode-cathode circuit to charge said condenser and then reconnectingsaid condenser be- .tween said oathode' and grid to impress a nega-.tive potential on said grid relative to said cathance with the chargeon said condenser to there'- I v by control .the current now insaid`anode-cathodo circuit, means responsive tomanual movement of saidtoast carrier tov toasting position for ci'iarg-'f` ing said condenserto a'predetermined value at the beginning of a toasting operation',afrjcsistorf.

connected across said condenser to thereafter jf gradually decreasethecharge on said condenser and thereby control said current ilow. andmeans responsive tol current flow in, said anode-cathode circuit forenergizing said heating elei'nentsA 'when control means.

ode, areisistor connected across said condenser to provide or gradualdecrease of said charge, and

.means responsive tocurrent iiow in said anodecathode circuit-due todecrease in said charge for releasing said holding means after apredetermined time interval, said resistor being variable to vary saidpredetermined time interval, and said toaster having a glow lampconnected be- -tween said conductors to indicate when said toaster isconnected to a direct currentlsource with the correct polarity for theoperation of said 'Y y ROBERT E. BARCLAY.

